Seat Belt Indicator Circuit Malfunction - Passenger

/ 9-5 (9650) / 2011 / 8. Body / Seat belt system / Fault diagnosis, fault symptoms / Seat Belt Indicator Circuit Malfunction - Passenger

Diagnostic Instructions

•	Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

•	Review Strategy Based Diagnosis for an overview of the diagnostic approach.

•	Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit	Short to Ground	High resistance	Open	Short to Voltage	Signal Performance
Passenger Seat Belt Switch Signal	1	2	2	2	-
Passenger Seat Belt Switch Low Reference	-	2	2	2	-
1. Indicator will remain ON with seat belt buckled. 2. Indicator will illuminate only for the bulb check.

Circuit/System Description

When an individual is sitting in the passenger seat the passenger presence sensor detects the individual. A signal to the SDM indicates a person is in the passenger seat. The SDM will turn the passenger seat belt indicator. The passenger seat belt switch is a 2-wire switch wired to the inflatable restraint sensing and diagnostic module (SDM) using a signal circuit and a low reference circuit. When the seat belt is unbuckled the switch is closed, and when the seat belt is buckled the switch is open. The SDM sends the status of the passenger seat belt via a hard wire to the hazard lamps switch. After receiving the message, the hazard lamps switch controls the illumination of the passenger seat belt indicator.

Reference Information

Schematic Reference

Seat Belt Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Seat Belt System Description and Operation

Electrical Information Reference

•	Circuit Testing

•	Connector Repairs

•	Testing for Intermittent Conditions and Poor Connections

•	Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1.	If the passenger seat belt indicator is always ON, even with no one sitting in the passenger seat, check the passenger presence detection sensor signal circuit for a short to ground.

2.

If there is not a short to ground in the signal circuit, replace the passenger presence sensor. Refer to Driver or Passenger Seat Cushion Pad Replacement (8-Way-Power) Driver or Passenger Seat Cushion Pad Replacement (2/4-Way) Driver or Passenger Seat Cushion Pad Replacement (6-Way Hybrid, 6-Way Hybrid Sport) .

3.	Ignition ON, with a scan tool perform the Passenger Seat Belt Reminder Indicator On/Off Control Function and verify the passenger seat belt indicator turns on and off.

4.	If the indicator is always ON or always OFF, refer to Seat Belt Indicator Malfunction.

5.	With the scan tool monitor the Passenger Seat Belt Status parameter while buckling and unbuckling the seat belt. The parameter should display Buckled and Unbuckled when buckling and unbuckling the seat belt.

6.	If the values do not change, refer to Seat Belt Switch Malfunction.

Circuit/System Testing

Seat Belt Switch Malfunction

1.

Note When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector. • B88 Seat belt switch • Seat belt switch harness connector • K36 SDM • SDM harness connector Ignition OFF, disconnect the harness connector at the B88 passenger seat belt switch.

2.	Ignition OFF, test for less than 5 Ω between the low reference circuit terminal 2 and ground.

3.	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal replace the K36 SDM.

4.	Ignition ON, verify the scan tool Passenger Seat Belt Status parameter displays Buckled.

5.	If not the specified value, test the signal circuit for a short to ground. If the circuit tests normal replace the K36 SDM.

6.	Install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2. Verify the scan tool Passenger Seat Belt Status parameter displays Unbuckled.

7.	If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal replace the K36 SDM.

8.	If all circuits test normal, replace the B88 seat belt switch. Refer to Driver or Passenger Seat Belt Buckle Replacement .

Seat Belt Indicator Malfunction

1.	Ignition OFF, disconnect the harness connector at the S26 hazard lamps switch.

2.	Test for less than 5 Ω between the ground circuit terminal 1 and ground.

3.	If greater than the specified range, test the ground circuit for an open/high resistance.

4.	Connect a test lamp between the control circuit terminal 4 and ground.

5.	Ignition ON, command the Passenger Seat Belt Reminder Indicator ON and OFF with a scan tool, the test lamp should turn ON and OFF while changing between the commanded states.

6.	If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal replace the K36 SDM.

7.	If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal replace the K36 SDM.

8.	If all circuit test normal, test or replace the S26 hazard lamps switch. Refer to Hazard Warning Switch Replacement .

Component Testing

1.	Ignition OFF, disconnect the harness connector at the B88 seat belt switch.

2.	Test for infinite resistance between the signal circuit terminal 1 and the low reference terminal 2, at the switch, with the switch in the open position.

3.	If less than the specified value, replace the B88 seat belt switch. Refer to Driver or Passenger Seat Belt Buckle Replacement .

4.	Test for less than 5 Ω between the signal circuit terminal 1 and the low reference terminal 2, at the switch, with the switch in the closed position.

5.	If greater than the specified range, replace the B88 seat belt switch. Refer to Driver or Passenger Seat Belt Buckle Replacement .

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for SDM and instrument panel cluster replacement, setup and programming

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